The digestibility of starch is usually determined in-vitro using methods involving digestion of the starch with α-amylase under pH and temperature conditions thought to mimick digestion in the human small intestine. However, there is evidence that such methods may overestimate the amount of resistant starch by as much as 100%. Methods used to estimate starch digestibility in-vivo include the breath hydrogen method and the measurement of the amount of carbohydrate in the ileal effluent of subjects with an ileostomy. The latter is considered to be the best in-vivo method which involves preparation of subjects with a polysaccharide-free diet the day before then consumption of the test carbohydrate with breakfast. Subjects collect ileal effluent during the day during which time they consume a polysaccharide-free diet. There is evidence that resistant starch consumed at breakfast is completely recovered in ileal effluent 8-10hr after consumption. The objective of this study is to determine the amount of carbohydrates in 3 commercially available starches (Hi-Maize® 260, Hylon® VII and Amioca corn starch) which escape digestion in the human small intestine.